The distances and times from a track meet for four schools are shown. School has the fastest average time per mile at the track meet.

Average time for West Middle was maximum.

Step-by-step explanation:

Average time for a track meet for schools =

For Eastbay Middle,

Average time per mile =

                                     = 6 minutes per mile

For Northwest Middle,

Average time =

                       = 5 minutes per mile

For South Central Middle,

Average time =

                       = 7 minutes per mile

For West Middle,

Average time =

                       = 8 minutes per mile

Therefore, average time for West Middle (8 minutes per minute) was maximum.

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9